JPH01157269A - Switching power source device - Google Patents

Abstract

PURPOSE:To contrive the energy saving of electric power, by a method wherein switching operation is controlled by setting and switching the value of a voltage, outputted to a load, so that it is changed from a rated voltage to a low voltage sequentially while detecting the operating condition of the load. CONSTITUTION:An electronic computer system, employing a switching power source device, is constituted of a CPU 1, a clock oscillator 2, a logical operation circuit unit 3, a memory 4, a power source device 5, control wires 12, 13 and the like. The value of a voltage, outputted to a load, is set and switched so that it is changed from a rated voltage, for example, to a low voltage sequentially while detecting the operating condition of the load by a voltage setting and switching means. The value of the set voltage is compared with the value of the voltage, outputted to the load, and switching operation is controlled by a control means so that the value of outputted voltage becomes the value of the set voltage. According to this method, the voltage, outputted to the load, is controlled so as to become the lowest voltage which can operate the load normally whereby the energy saving of electric power may be contrived.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to an energy-saving type switching power supply device.

(Prior Art) In general, various electronic devices use switching power supplies as their power supply means. In the electronic device described above, a rated voltage is set, and a predetermined rated voltage is supplied in the switching power supply by, for example, feedback control.

In each electronic device mentioned above, for example, in an electronic computer system, the power supply voltage supplied to the logic circuit is +5. It is set to Ov.

And this +5. The system is operated normally by supplying Ov by a switching power supply.

By the way, the above-mentioned power supply voltage may change depending on the usage condition of the power supply, and the rated voltage is +5. There are cases where Ov cannot be obtained. Therefore, as the voltage margin,
For example, if the rated voltage is +5', OV,
．． ±5% of Ov, that is, the lower limit is -4°75V, and the upper limit is +5.25V.
, +5. A voltage margin test is performed using OOV and a voltage of +5.25V to check whether the system operates normally at each voltage. In general use, it is set to operate at +S and OV.

In addition, in recent years, there has been a demand for energy saving, but when using multiple electronic devices such as the system using the conventional switching power supply mentioned above, it is natural that
There are problems with high power consumption (and high electricity bills),
Further, as described above, even when the system is normally operated at a voltage lower than the rated voltage, the system is configured to maintain the rated voltage.

(Problems to be Solved by the Invention) The present invention is intended to solve the above-mentioned problems, and it is an object of the present invention to provide a switching power supply device that can effectively save energy.

[Structure of the Invention] (Means for Solving the Problems) The present invention is constructed focusing on the fact that the system operates normally even at a voltage lower than the rated voltage, and the input DC is switched to obtain the desired voltage. In the switching power supply device configured to convert, rectify and smooth the voltage to be supplied to the load, the switching power supply device includes voltage detection means for detecting the voltage output to the load, and voltage detection means for detecting the voltage output to the load; Voltage setting switching means for detecting an operating state and setting and switching the voltage value according to the operating state, and comparing the set voltage value set by the voltage setting switching means with the voltage value detected by the voltage detecting means. control means for controlling the switching operation so that the voltage value detected by the voltage detection means becomes the set voltage value output from the voltage setting switching means, and the voltage output to the load is controlled by the load. The voltage is the minimum required for normal operation.

(Function) The present invention detects the operating state of the load using a voltage setting switching means and changes the setting of the voltage value output to the load so that the voltage value is sequentially lower than the rated voltage, and the set voltage value and the load are adjusted. The switching operation is controlled by the control means so that the output voltage value becomes the set voltage value by comparing the output voltage value, and the voltage output to the load is set to the minimum value for the load to operate normally. Since it is made to be a voltage, energy saving of electric power can be effectively achieved.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIG. 1 is a block diagram for explaining an electronic 51 computer system using a switching power supply device according to an embodiment of the present invention.

In the figure, 1 is a CPU, 2 is a clock oscillator, 3 is a logic circuit section of CPU 1, 4 is a memory, 5 is a power supply device, and 6
7 is a bus for supplying the +5V voltage from the power supply device M5 to the CPU 1, 7 is the GND line of the bus 6, 8 is a bus for supplying the +12V voltage from the power supply device 5 to the CPLll, 9 is the bus 8 bus GND line, 10 is 11 from power supply device 5
A bus for supplying a voltage of 2V to the CPU 1, 11 is a GND line of the bus 10, 12.13 is a control line, and the control line 12 is a control signal that instructs the voltage value set from the CPU 1 to the power supply device 5. Output. Further, the control line 13 outputs a control signal from the power supply device 5 to the CPUI. 14 is AC
It shows the power supply of looV.

FIG. 2 is a circuit diagram for explaining the switching power supply used in the computer system of FIG. 1.

In the figure, 21 is a filter, 22 is a rectifier, 23 is a smoothing capacitor that stores the rectified voltage, 24 is a switching transistor, 25 is a snubber circuit that consumes the energy stored in the transformer when the transistor 24 is turned off, 26 performs pulse width modulation control of the switching of the transistor 24, and also controls each output voltage (+5V, +
12V, -12V), and further receives operation information indicating whether each part in the CPU 1 described in FIG. 1 is operating normally with the above-mentioned output voltage,
A control unit 27 which switches the pulse width modulation of the switching of the transistor 24 so as to switch the output voltage based on this operation information is a single-input, multiple-output type transformer.

Also, Dll, D12, D21, D22, [)nl, O
n2 is a rectifier diode on the secondary side of the transformer 27, C1,
C2...On is a smoothing capacitor, Ll, L2...1
．． n indicates a coil that reduces the peak value of the current flowing through the transistor 24 and also reduces the ripple voltage.

In this circuit, when AClooV passes through a filter 21 and is full-wave rectified by a rectifier 22, a charge corresponding to approximately 140V is accumulated in a capacitor 23.

On the other hand, the operating voltage +V is applied to the control section 26, and the control section 26 applies an on-pulse to the base of the transistor 24 to turn on the transistor 24.

At this time, the charge of the capacitor 23 is A-+8-+C→D
−+E−+F→G −>H→ The current flows in the direction.

In addition, each output J1K on the secondary side of the transformer 27...
・A voltage with the ratio of primary to secondary winding is generated in L, diode 1) 11, [) 21-[) nl, coil 11, L2
...A current flows through ln and reaches the load. Here, the components of the ripple current are accumulated as charges in the capacitors CI, 'C2, . . . , Cn, and each outputs a DC current.

Furthermore, when the transistor 24 is turned off, the excitation current C→D of the transformer 27 tends to continue to flow, and this energy and the energy stored in the leakage inductance are consumed in the snubber circuit 25.

At this time, the coils 1 and L of each secondary circuit of the transformer 27 are
2... A back electromotive voltage is generated by the energy stored in Ln, and the coil Ll is generated during the period when the transistor 24 is on.
, L2...In continues to flow through the diodes D12, D22...[)n2, and the ripple current that reaches the load flows through the capacitors C1, C
2...Cn k: Accumulated as WR load.

Note that when the voltage on the secondary side of the transformer 27 decreases, the pulse width of the on-time of the transistor 24 is increased by the pulse width gain wJ function of the control circuit 26 in order to increase the energy sent to the secondary side. Also, on the contrary, transformer 27 no 2
When the next-side voltage increases, the control circuit 26 reduces the pulse width of the on-time of the transistor 24. These effects stabilize the DC output on the secondary side.

Then, when the stabilized DC output is output to MSQ and U, current flows to each load.

Next, the configuration of the control circuit 26 will be explained. ``The control circuit 26 includes a driver 28 that applies a driving pulse to the base of the transistor 24, a pulse register 29 that holds the driving pulse, and a circuit in which control data and ``a plurality of reference data for generating a plurality of voltage values'' are written. ROM30 included
, a RAM 31 serving as a work area, and a microcomputer 3 having a pulse width modulation function and a voltage setting switching function for switching the output voltage based on operation information from the CPU 1.
2, a voltage register 33 that holds the voltage value on the load side as binary data, an AD converter 34 that converts the voltage on the load side into binary data, and amplifies the voltage output to a predetermined load. An amplifier 35 is provided.

The pulse register 29 has a storage capacity of 8 bits, and the pulse register 29 is read and written by the microcomputer 32. Bit 7 of pulse register 24 is L
SB, which is connected to the driver 28 and used to determine the switching pulse width. Also, bit 6 is the first
Operation information indicating the operating state of the CPU 1 (information indicating normal operation or information indicating abnormal operation) is received from the CPUI explained in the figure. In other words, from CPU1 to control line 1
2, the operating information data transferred bit serially is stored in bit 6 of the pulse register 24, this data is read by the microcomputer 32, and the CPU
Recognize the operating state of 1. Further, bit 5 of the pulse register 24 is used to send a control signal such as clock change information to the CPLJI via the control line 13. That is, the microcomputer 32 writes predetermined data to bit 5 of the pulse register 29, thereby transmitting predetermined information to the CPUI via the control line 13 in a bit serial manner.

Further, FIG. 3 is a diagram showing the switching pulse waveform output to the base of the transistor 24, and A is a waveform when turning on the transistor 24 for a time T1 and supplying maximum energy to the transformer 7 in FIG. B shows a waveform when the transistor 24 is turned on for 12 hours and a small amount of energy is supplied to the transformer 7.

Next, the operation of the switching power supply device configured as described above will be explained using FIG. 1 and FIG. 2.

First, when AClooV is supplied to the power supply 5, the power supply 5 connects the bus 6.8.10 with DC+5V,
+12V and -12V are output and supplied to CPtJl.

The CPU is then brought into a state where it can perform predetermined operations with each voltage. Thereafter, operation information and predetermined processing information on the CPU 1 side, which is a load, are serially transferred from the CPU 1 via the control line 12 with a predetermined pulse width, and are input to bit 6 of the pulse register 29. Thereby, the microcomputer 32 reads the pulse register 29 at regular intervals to recognize the operating state of the CPU 1. Also, it is recognized from the processing information that there is a voltage switching request on the CPU side.

When the microcomputer 32 recognizes, for example, a switching request to switch the output voltage +5■ to +4.75ν, the microcomputer 32 sets the time for setting the SB pins 1-7 of the pulse register 29 to 0 in a similar manner; (shorten the on-time) and reduce the energy supply to the secondary side through the transformer 7. After that, the microcomputer 32 inputs the voltage between a and b into the amplifier 35, converts it into an AD converter 34, and converts the voltage between the voltage register 3
3, read the voltage between a and b of the digital signal.

When the read voltage value is higher than the specified 4.75V, the microcomputer 32 sets the LSB bit 7 of the pulse register 29 to 0.
Control to make it shorter. 4, 75 instructed to the contrary
If the voltage between a and b is lower than V, the microcomputer 32 sets the LSB bit 7 of the pulse register 29 to 0.
Control the setting time to be longer. Therefore, the output voltage of bus 6 is controlled to be constant +4.75V. This causes bus 8 to go from +12V to +11.4V, and bus 10 to go from -112V to -11.4V.
Controlled by V.

After this, the CPU1 goes to the above-mentioned L level +4.75V, +11.
For example, a test program is executed at voltages of 4V, -11, and 4V to check the operating state.

Thereafter, operation information and processing information are output from the CPU 1 to the power supply device 5 via the control line 12.

Then, it is recognized from the operation information whether the operation is normal or abnormal. For example, if the test program operates normally and there is a request to lower the voltage in the processing information, each bus 6.8 .10(7) Voltage +4.5
V, +10.8V, -10.8V, and check whether it operates normally with these output voltages. If the abnormal operation results in an error, the operation information from the CPU includes data indicating the abnormal operation, and this changes the voltage of each bus 6.8.10 to, for example, +4.68V, +11, IV. , -11, and IV, and check whether it operates normally with these output voltages.

In this way, the limit voltage at which the CPUI operates normally is detected and set to a voltage at which the system operates stably.

Therefore, when operating normally at the above-mentioned voltages, the power consumption is approximately 1.5% less than at the rated voltage.

In addition, in the above-mentioned operation, in order to stably operate the CPU 1, which is the load side, at a low output voltage, the frequency of the clock excavator 2 of the CPU 1 is lowered, and the clock width is increased by switching from clock 1 to clock 2. The control information may be sent from the microcomputer 32 #11 to the CPUI via the control line 13, or may be switched manually using a switch or the like, or automatically using the CPLI 1.

Therefore, in this embodiment, since the load is configured to supply the minimum voltage for normal operation, it is possible to effectively save energy.

In the above-described embodiment, all voltages on the load side are switched, but a predetermined voltage on the load side may be switched as shown in FIGS. 4 and 5. In addition, in these figures, A C/D C indicates the filter 21, rectifier 22, smoothing capacitor 23, and snubber circuit 25 shown in FIG. 2, and S W 1S W + and S W 2 indicate the transistor 24. T, T+, T2 represent transformers, RECT1~R
ECT3 indicates a rectifier diode, FILT1 to FILT3 indicate smoothing capacitors, and C0NT1 and C0NT2 are drive signal generation circuits that supply drive signals to the switching circuit, and output voltage as a feedback signal. The input voltage is compared with the built-in M quasi-voltage, and a drive signal pulse train having a desired duty cycle is generated from the error signal of the difference. In addition, C
0NT1 is the control circuit explained in FIG.

In FIG. 4, in this embodiment, the voltage on the +5V load side is configured to operate at a voltage lower than the rated voltage, similar to the embodiment in FIG. It is configured to work with.

Therefore, in this embodiment, when it is not possible to operate at a voltage lower than the rated voltage as a whole, only a part of it can be operated at a voltage lower than the rated voltage, and the same effect as in the embodiment described above can be obtained. You can do it.

In addition, in FIG. 5, in this embodiment, the voltage output to the load on the +5V side is connected to C0NTl on the secondary side of the transformer.
(control circuit).

Therefore, in this embodiment as well, like the embodiment shown in FIG. 4, when the entire device cannot be operated at a voltage lower than the rated voltage, only a part of it can be operated at a voltage lower than the rated voltage.

In the above-mentioned embodiments, a switching power supply HM particularly applied to an electronic computer system has been described, but the present invention is not limited to these embodiments, and can be applied to information equipment using electronic components such as ICXLSL. In addition, in the above-mentioned embodiment, when switching the rated power supply, the setting is
Although this is done by the PU or MPU, it may also be done by an external source, such as a manual key, or an operator may check whether the load is operating normally.

[Effects of the Invention] As explained above, the switching power supply device of the present invention has the following effects:
While detecting the operating state of the load using the voltage setting switching means, the voltage value output to the load is switched to a voltage that is sequentially lower than the rated voltage, and the set voltage value and the voltage value output to the load are compared. The switching operation is controlled by the control means so that the output voltage value becomes the set voltage value, and the voltage output to the load is the minimum voltage at which the load can operate normally. Energy saving of electric power can be effectively achieved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram for explaining an electronic computer system using a switching power supply device according to an embodiment of the present invention.
FIG. 2 is a circuit diagram for explaining the switching power supply tray of FIG. 1, FIG. 3 is a diagram for explaining the switching pulse waveform of the transistor in FIG. 2, and FIG. 4 is another embodiment of the present invention. FIG. 5 is a diagram for explaining a switching power supply according to still another embodiment of the present invention. 21... Filter, 22... Rectifier, 23... Rectifying capacitor, 24... Transistor, 25... Snubber circuit, 26... Control circuit, 27... Transformer,
28...driver, 29...pulse register, 32
...Microcomputer, 33...Voltage register, 34...AD converter. Applicant Toshiba Corporation Representative Patent Attorney Sasa Suyama −

Claims (1)

[Claims] In a switching power supply device configured to switch input direct current, convert it into a desired voltage, rectify and smooth it, and supply it to a load, a voltage detection means for detecting a voltage output to the load; Voltage setting switching means for detecting the operating state of the load at the output voltage value and switching the setting of the voltage value according to the operating state;
The set voltage value set by the voltage setting switching means is compared with the voltage value detected by the voltage detecting means, and the voltage value detected by the voltage detecting means becomes the set voltage value output from the voltage setting switching means. A switching power supply device comprising a control means for controlling the switching operation so that the voltage output to the load is a minimum voltage at which the load can operate normally.